The Center of Gemological Studies (C.G.S) was established by Eli Dori in 1979 and offers group & individual gemological courses according to the students preference.

This is the most prestigious, affluent and respected gemological center in the Israeli Diamond Center and has taught thousands of students that are working in the diamond industry today. The C.G.S was chosen by the Israeli Diamond Center to teach the future Members the gemological course.

Eli Dori, is a graduate gemologist (G.G) for the last 40 years, he graduated outstandingly in residence of GIA.Hadas Dori Bar Moshe graduated gemologist with experience of over 25 years. They will provide you a comprehensive and intensive gemological course, in an intimate, pleasant and patient environment, that suites and is adapted to every student.

If you are interested in studying, developing and obtaining experience in the diamond field, as well as requiring the best professional knowledge and practical grading, our center is the right place for you!

Gemology CourseGrading And EvaluationOf Polished Diamonds

The course is taught over a period of 50 hours that include theoretical material as well as practical work which includes the sorting of over 100 polished diamonds by microscope and by loupe. The method by which sorting is taught is according to the GIA and their terminology.

Lecture:The Secrets of the Diamond

A captivating and unique lecture about diamonds and the diamonds industry. From Marlyn Monro to "Mazal and Bracha" – Hadas Dori Bar Moshe will take you on a spectacular and entertaining journey to the world of diamonds and it's industry. A lecture that will reveal the hidden secrets and behind the scene stories of this intriguing world.

What are graining lines in the diamond? how do they effect the clarity, the quality and the color of the diamond? Graining Lines in the diamond, are a natural part of the diamond. They affect the clarity and the

How can we differentiate between internal inclusions and cavities , to external imperfections and dirt? Here are several methods of evaluating the diamonds that will help you see the differences between the clarity characteristics and by that evaluating the clarity